Every great teacher was once a kid asking the same question five times.

Expertise erases its own history, which is why competent people can look like a separate species. Whoever is explaining it fluently was once the slowest in the room, asking the same thing over and over, and that stage does not survive into the finished version you are watching. Needing it repeated is not evidence you are unsuited to this. It is the ordinary way in.

So ask the fifth time. Ask in writing if out loud is worse, or ask one person afterwards rather than the whole room. And when you are the one who knows, answer like somebody who remembers.